600 watts what??? Continuous, Program, Peak?800 watts what??? Continuous, Program, Peak?Before you can look at doing the calculationsfor amplifier selecton, as describbed in other posting of this forum, you need to know what the power spec is actually telling you.

Zenzilla, This is a reply to a Post further down. I modified it a bit to fit your scenario.

Let's start with the Basics.There is a kinda rule of thumb that to properly power your Speakersyou take the RMS / Continuous rating and multiply it by 1.5 to 2x Another way is to double the RMS /Continuous rating and then multiply that by 0.8 and 1.25 for the power needed.There is even another that you can find on this website that states:Crown paperThat if properly limited, you should have an amplifier that can reach tothe actual "Peak" of the Speakers.The Crown article goes on to say:

"If you are mainly doing light dance music or voice, we recommend that the amplifier power be 1.6 times the Continuous Power (RMS) rating per channel. If you are doing heavy metal/grunge, try 2.5 times the Continuous (RMS) Power rating per channel. The amplifier power must be rated for the impedance of the loudspeaker (2, 4, 8 or 16 ohms)."

Now let's take the first formula and apply it to your Speakers.

1) The TR1503 is rated at 600 watts Continous / RMS." (wrms) The 1.5x is 900wrms / the 2x is easy, it's double at 1200wrms.That's why you see the 1200 watts max power Amp recommended.So your Power Amp should fall somewhere in this range of 900 to 1200wrmsat 8 ohms (if per Channel or one amp Bridged at 8 ohms)If you paralleled 2 speaker cabs to get to 4ohms, the power would now be spread over the 2 speaker Cabs, and you would double the numbers above. So you would want 1800wrms to 2400wrms.This would be on a Bridged amp (or per channel if you had 2 cabs per channel) at 4ohms.

2) The SW1801 Sub is rated at 800 watts Continous / RMS.The spec should also say 1600 max recommended power, so I don't know where they come up with 1000, must be a typo!Anyway, taking info from above this means you need:1.5x at 1200wrms to 2x at 1600wrms at 4ohms per channel or Bridged.It is not a good idea to parallel two 4ohm cabs to get to 2ohms.Even though some amps will give a 2ohm spec, it is usually shied away from but you still have to do what you have to do.

The K2 is 500 wrms at 8 ohms, not enough for your TR1503 in Stereo.The K2 at 4 ohms is 800 wrms, still not enough for your Sub, SW1801.

You have some decisions to make.

You can run your tops in Stereo, but the 900 to 1200 watts RMS per channel at 8 ohms is a tough order! You can check out the CE4000, or the I-Tech's, or put 1 Bridged amp per cab.You could also run your top cabs Mono (Parallel two 8 ohm 1503 Cabs to get to 4 ohms) and use an amp like the XS700 Bridged at 1900wrms at 4ohms. That would be 950wrms per cab. Respectable, even though it's closer to the 1.5x than the 2x rating.

The Subs SW1801 is not as bad because the cabs are 4 ohms.You could use a CE4000 (great Sub Amp) it puts out 1200 wrms at 4ohmsper channel.

So, the above scenario would net you 950 watts per cab on your Tops and 1200 watts per Sub cab. I like to have more power on my Subs than on the Tops.

Another scenario that will keep your top cabs Stereo would be to use 2 CE4000's, one on your top cabs, at 800wrms per channel per cab at 8ohms. Slightly under the 1.5x rating of 900wrms but only by 100 watts. The other CE4000 would still on your Subs Stereo / per channel. In your situation I think that two CE4000's would be better than two K2's, possibly less money as well!The CE4000's are also BCA technology as the K2 but with a Power Factor Correction (PFC) Power Supply, that the K2's do not have. Check them out.I never hear the variable speed fans on mine.

Obviously you can use whatever amps and scenario that you want as long as your power scheme falls somewhere within the above guidelines.Note that these are Guidelines, but be it known, that if you run underpowered to your speakers you may want to push the System and have some clipping going on!Always set your "Gain Structure" correctly!

Howdy, We sometimes use our CE4000 / PA in a rehearsal room the size of a small bedroom, well, in fact it is a small bedroom. LOLI never notice the fan, and I stand in front of it.There is one fan per amp.Check here for more info on the CE4000 - CE 4000 Data Sheet

I would say, go by a local music store or Guitar Center, where they always have them hooked up and take a listen.Maybe you have more sensitive ears than mine, and if you hear it see how far away you need to be, to not hear it! I'm sure that most places would even take one out of a box and plug it in, no speakers have to be hooked up to it, to turn it on. I am very happy with mine!The fans are very quiet though, plus they are on the back of the amp.If the amp is in an Amp Rack it is even less to hear.

The 2 fan's on my new XS900 run continuosly and are very noticeable! The XS's are not quiet amps.

When not gigging my PA is setup in my Living room, makes CD's / DVD's sound great! At a quiet segment in a movie (pre XS900) I did not hear the CE4000.

Good Luck, BudPS. I am a gigging musician, and "Live Sound" individualand do not work for Crown.

This in an inexpensive and ideal power-match for your speakers (with no fans)!

I stongly recommend against the (4) bridged K2's. That configuration can very easily overpower/destroy your speakers.

If you must have left-right channel separation, consider: (2) Crown K1's (bridged-mono) for the tops: 1100w each speaker ***Or (2) CE 1000's (bridged mono): 900w each speaker (variable fans) and much easier on the $$$!